1. Field
This disclosure relates generally to test methods and systems, and more specifically, to methods and systems for testing analog-to-digital converters.
2. Related Art
Many of today's system on chip (SoC) devices include converters such as an analog-to-digital converter (ADC). An ADC generally samples received analog voltages and converts the sampled voltages into digital values. The resolution or precision of an ADC is typically dependent upon the application of SoCs. For example, if the ADC was used to determine a temperature in a consumer temperature sensing application, then a typical resolution might be 8 bits. Higher resolution ADCs require higher precision and are generally more sensitive to environmental conditions such as circuit noise, temperature, operating voltages, and so on.
Traditionally, ADCs are tested by providing test input voltages representing each of the conversion result values. To account for noise and to precisely calculate the error, the test input voltage is varied in multiple steps in the range of each conversion result value. Because this test technique is time consuming, which leads to prolonged test times and requires expensive test equipment, it is desirable to perform ADC testing within a system or application to assist in system debug efforts, for example.